I have accepted DRK has changed a lot from 3.0 to 4.0....but some love and tweaks would go a long way...

The Blackest Night - Increase this to 7 second duration just because 5 seconds is so tight...If I have latency or not 100% timed it can go to waste...the current 15 sec CD is more than sufficient as the deterrent to not outright use on CD is the MP cost.

Have Delirium apply a 10% reduced damage taken to blood price but at the same time reduce blood price duration by 5 seconds. Can give a choice between having a longer blood price or mitigation.

Change the effect of Dark Passenger to something worth the high MP cost of using it with DA - maybe have it supply blood gauge as a unique effect. Can allow us to chain with Quietus as something of an AoE rotation.

I think some tweaks could help a lot with DRK...and one more mitigation tool will help with survivability in raid. Quietus MP restore is nice for dungeon tanking but has little use in raids.